KR20030020918A - Polymer Filaments Having Profiled Cross-Section - Google Patents

Abstract

The invention provides a profiled polymer filament having an open hollow cross-sectional shape normal to the longitudinal axis of the filament, wherein the cross-section is dimensioned to prevent the filament from interlocking with a second filament of the same cross-section. The invention also provides methods of manufacture of such filaments by melt spinning a polyamide, and spinnerets suitable for use in melt spinning such filaments.

Description

Polymer Filaments Having Profiled Cross-Section

Synthetic polymers, in particular textile fibers or filaments from polyamide polymers such as nylon 66 and nylon 6, and multifilament yarns melt-extruded from the same polyamide polymer, are typically partly oriented yarns (POY) and stretch yarns for apparel. It is prepared as. POY has an elongation at break greater than about 55%, and the drawn yarn has a lower elongation. In the case of each filament comprising either type of multifilament yarn, for example POY and drawn yarn, the most common cross sectional shape is circular. Modifications to the individual filament cross-sectional shapes include three- or six-leaf type published in Japanese Patent Publication 01-20243 (Nihon Ester KK), US Patent No. 5,834,119 (Roop). Hollow polyamide filaments having a spherical elliptical cross section, and one longitudinal pore disclosed in US Pat. No. 5,604,036 (Bennett et al.).

The above examples are all known variants of POY and drawn yarns that all have a heteromorphic cross-sectional shape. Filaments with cross-sectional shapes other than round provide colorful visual aesthetics, opacity and cover, and lighter weight to multifilament yarns for fabrics and apparel. Yarns from hollow filaments, such as those of the last mentioned US patent, provide lighter weight fabrics and garments and improved thermal insulation compared to conventional circular filaments that do not have longitudinal pores. Hollow filament yarns are particularly suitable for apparel applications when bulky yarns are organized by conventional methods such as air jet texturing (AJT) and false twist texturing (FTT). Hollow flat yarns for direct use in the field of weaving are also known.

Partially oriented and flat nylon yarns with high porosity hollows are all disclosed by Bennett et al. However, filaments having longitudinal pores are difficult to close completely upon spinning and may also be substantially deformed during tissue processing. This can lead to the letter 'type C' filaments and / or crushed tubular cross-sectional shapes. The letter C filaments can be densely packed together with the loss of open space between adjacent filaments. In addition, the letter C cross section filaments and crushed tube cross sections result in undesirable thread and fabric properties as a result of the event. Increased fabric density and reduced thermal insulation of fabrics and garments are particularly undesirable properties. In addition, yarns from filaments with varying amounts of ruptured longitudinal pores result in dyed fabric streaks, and free filament pores provide a place for growth to opportunistic bacteria.

It has now been found that the disadvantages listed above can be overcome by the preparation of polymer filaments with new cross sections.

The present invention provides a release filament from a synthetic polymer having a "open hollow" cross sectional shape perpendicular to the longitudinal axis of the filament. The cross section has the dimensions necessary to prevent the first filament from intertwining with the second filament having the same cross section. This is wider than the spacing between the regions near each end of the cross section forming an opening in the open hollow cross section.

Release cross-sectional filaments of the present invention are provided by an extruded capillary having a novel shape and design. The filaments of the invention are produced directly by melt extrusion of the synthetic polymer through a multi-capillary spinneret plate. The term “open hollow” generally refers to a C having a hollow center and a solid region having a wall portion extending around the hollow center for enclosing the hollow center but having an opening connecting the center and the outside of the filament on one side of the wall. Type or U cross section. The opening is narrower than the diameter of the hollow center, forming a throat or clamped portion between the hollow center and the outside of the filament.

Preferably, the filament comprises a faithful portion that substantially surrounds the central hollow area. The opening runs from the outside of the filament to the central hollow area. The faithful portion includes a leg that ends with a foot. The facing surfaces of the foot form the neck of the opening (the narrowest dimension). The neck of the opening is for the fan angle alpha (α) of 90 degrees or less, more preferably 75 degrees or less and most preferably 10 to 60 degrees. As shown in FIG. 1, the radial angle alpha (α) is an angle formed between two lines R ₁ and R ₂ derived from the point C. FIG. Point C is a point lying on the inner surface of the faithful portion of the filament furthest from the baseline R ₃ connecting the ends of the foot tangentially. Each line R ₁ , R ₂ lies tangent to a point on the facing surface of the foot that extends from point C to form the neck of opening D. The faithful portion is about the same fan angle as 360 ° -angle alpha (360 ° -α). Preferably, the faithful portion of the cross section is about a fan angle of at least 270 degrees. More preferably, the faithful portion is for a fan angle of 300 degrees or more.

The filaments according to the invention are suitable for preventing interlocking or stacking of the filaments. For example, engagement such as a hook of two cross sections resulting from the insertion of one end of the faithful portion of the first filament cross section through the opening in the cross section of the second filament is prevented. This can be achieved as previously described by making the faithful portion of the cross section for a large fan angle so that the opening in the filament cross section is very small. Alternatively, or in addition, the ends of the faithful portion of the cross section may be enlarged to inhibit insertion of other filaments into the opening.

The faithful portion of the cross section in the filament according to the invention may form one continuous curve. Preferably, the cross section comprises a "central arcuate" or base portion with first and second ends and two side or "leg" portions. The leg portion extends in substantially parallel relationship from the first and second ends of the central arched portion.

In a preferred embodiment, such as the filament cross-sectional geometry shown in FIG. 1, the filament cross-sectional shape is first parallel to the arcuate portion 1 (extending horizontally in FIG. 1) and the first and second generally parallel to the arcuate portion in the center. It is characterized by one elongated leg portion 2, 3 (extending vertically in FIG. 1). The distal portion of each leg 23 opposite the junction with the central arcuate portion 1 forms an enlarged foot portion 4. Each foot portion 4 features dimension F, which is the length of the foot, as shown in FIG. The release filament cross section has an open center. This open part is bounded by the leg parts 2, 3 and the central arcuate base part 1 on three sides. The foot portion 4 is oriented in a substantially side-by-side relationship that forms an opening between the facing surfaces of the foot portion having the dimension D leading to the open portion as shown in FIG. 1. Dimension D is smaller than dimension F. As a result, the foot on either leg of the release filament may be any other identical to prevent one foot of the first filament from entering (entangled with each other) between the legs of the other filament in the multifilament yarn bundle, as illustrated in FIG. 2. It is large enough for the opening between the pair of legs of the filament.

Preferably, the polymer used to form the release polymer filaments according to the present invention is polyamide. More preferably, the polyamide polymer has a relative viscosity by formic acid method greater than 40, even more preferably the relative viscosity of polyamide by formic acid method is in the range of 46 to 56. Preferably, the polyamide is selected from the group consisting of nylon 66 and nylon 6 and copolyamides.

Preferably, the single filament line density is 0.5 to 20 dtex, more preferably 2 to 10 dtex. Most preferably less than 4 dtex. Preferably, the filament cross-sectional shape is substantially constant along the length of the filament. Preferably, the filament nonuniformity is less than 1 Uster%.

The release filaments according to the invention provide lighter unit weight yarns, in particular after tissue by AJT (Air Jet Texturing) or FTT (Fall Twist Texturing). The yarn contains a high free volume of space. The volume of space contributes to the improved thermal insulation of the fabrics and garments made from this yarn. When knitted or woven into a fabric, the yarn provides a less dense fabric than a similarly constructed fabric only from circular cross section filaments. In addition, the yarns exhibit high moisture wicking ability.

Accordingly, the present invention further provides a multifilament yarn wherein at least a portion consists of a release filament according to the invention.

Preferably, the yarn comprises at least 10% by weight, more preferably at least 25% by weight, even more preferably at least 50% by weight of the release filaments according to the invention, most preferably consisting essentially of said filaments.

The invention further provides an article in which at least a portion consists of a thread according to the invention. Preferably the article comprises a fabric knitted or woven from a thread according to the invention.

A further aspect of the invention is a spinneret for producing a release open hollow filament according to the invention by melt extrusion of the polymer into filaments. The spinneret includes a plate having upper and lower surfaces connected by capillary assemblies. The shape, size and configuration of the capillaries are suitable for melt spinning of the filaments according to the invention. Specifically, each capillary comprises two adjacent segments as in FIG. 3A, whereby an open hollow filament longitudinally with respect to the axis of the filament when the molten polymer stream from each segment merges at points between the segments A cross section is obtained, or each parent tube has an open hollow transverse cross section as in FIG. 3B.

A preferred spinneret plate for the production of release open hollow filaments is that each capillary of FIG. 3A consists of two segments. Each segment consists of a straight length portion 30 having a junction at each end with a pair of protruding portions. At the first end, the pair of protruding portions have the same area, each comprising straight portions 31, 32 ending with round portions 33, 34. At the second (first opposite) end there are projecting portions having a pair of floating areas. The protruding portion of the first floating area consists of a straight portion 35 and the rounded portion 36, and the protruding portion of the second floating area consists of the straight portion 37 and the rounded portion 38. Therefore, each segment of the capillary has two equal protrusions at one end and one at the opposite end. The unique (longer) protrusions present on each segment consist of a straight portion 37 and a rounded portion 38. Preferably, each capillary segment is a mirror image of the other segment. More preferably, each segment is an invisible mirror image of another segment, for example as illustrated in FIG. 3A. The mirror image relationship that cannot be superimposed means that each segment has the same handiness in the same way as the human left and right hands.

An open hollow filament cross section perpendicular to the longitudinal axis of the filament is obtained when the molten thermoplastic polymer stream from each capillary segment merges at a point between the protruding portions of the two segments. That is, the open hollow filament cross section of the present invention is formed when the molten polymer stream merges between the facing rounded portions 38 of the left and right capillary segments shown in FIG. 3A.

If the capillaries themselves have an open hollow cross section, the capillary illustrated by FIG. 3B is a preferred spinneret geometry cross section for the production of a release open hollow filament. Each capillary has a cross-sectional shape comprising a first straight portion 40 having a first end and a second end opposite each other. It is the second straight portion 48 and the third straight portion 50 that bifurcate from the first end of the first straight portion 40. The second straight portion 48 ends with a rounded portion 49 and the third straight portion 50 extends to two forks, from the fourth straight portion 53 and the fifth straight portion 52. ) Is extended. The fourth and fifth straight portions have a floating area, each ending with rounded portions 54 and 51. Similarly, it is the sixth straight portion 41 and the seventh straight portion 43 that bifurcate from the second end of the first straight portion. The sixth straight portion 41 ends with a rounded portion 42 and the seventh straight portion 43 extends to two forks, from which the eighth straight portion 46 and the ninth straight portion 44 ) Extends, the eighth and ninth straight portions have a floating area, each ending with rounded portions 45 and 47.

In a further aspect, the present invention provides a process for producing a drawn yarn and partially oriented yarn (POY) having a modified filament cross section according to the present invention. In general, the process comprises the step of extruding a polyamide melt, typically from nylon 66 or nylon 6, from 40 to 60 RV (measured in formic acid), and preferably from 48 to 52 RV, to form a plurality of filaments. do. The spinneret according to the invention is kept at a temperature selected from the range of 245 to 295 ° C., more preferably it is 280 ° C. Cooling in an air stream across the plurality of filaments extruded through the spinneret forms a solid filament. These filaments can be treated with oil, converged, knitted and stretched, or left unstretched before winding the multifilament yarns at speeds greater than 3000 meters / minute (m / minute).

Referring now to the schematic method of FIG. 5, the drawing yarn is made along path A. FIG. The molten polymer 10, polyamide, is pumped into the spin pack 20 to force the spinneret plate 30 to form a filament 40. The newborn filaments are cooled with a traversing air stream 50 having an air velocity of about 0.15 to 0.5 meters / minute. The cooled filaments are converged into the yarn 60 and preferably at 70 the oil and water finish is added to the resulting yarn bundle. The yarn 60 advances through the first air knitting jet 80 into a blended yarn 90. The yarn 90 is sent to the first goth 92 (feed roll) and its associated separator roll, wrapped several times to prevent slippage, and then the second goth 94 (stretch roll) and its associated separator Send to roll. The stretching roll 94 is moving at a surface speed of 60 to 100%, preferably 80%, greater than the surface speed of the feed roll 92. Thereby the yarn bundles are preferably elongated (longer and thinner) by about 1.8 times in total to reduce the overall yarn titer to form the yarn 100. The stretching yarn 100 is preferably treated by the relaxation device 110 to fix the stretching and to relax the yarn as is conventionally practiced in the art. Any known relaxation device may be used, for example steam, heating fluid, hot tubes, hot shoes, heating rolls. The relaxed yarn bundle 120 optionally passes through the second knitting jet 130 and after being optionally oiled the relaxed yarn 140 has a winding speed of 3000 meters / minute, more preferably about 3800 meters / minute. It is wound on a furnace tube 150. The resulting stretch yarn has an elongation of 25 to 45%, preferably 40 to 45% and a toughness of 35 to 45 cN / tex.

Alternatively, referring now to the schematic method of FIG. 5, a partially oriented yarn POY is made along path B. FIG. The molten polymer 10, polyamide, is pumped into the spin pack 20 to force the spinneret plate 30 to form a filament 40. The newborn filaments are cooled with a traversing air stream 50 having an air velocity of about 0.15 to 0.5 meters / minute. The cooled filaments are converged into the yarn 60 and preferably at 70 the oil and water finish is added to the resulting yarn bundle. The seal 60 is run through a vapor atmosphere containing interfloor tube 75, as is known in the art. The steamed yarn 85 is mixed at 80 and partially wrapped around the godet 82 and the godet 84, which controls any change in winding tension that the yarn may experience. The yarn 115 is wound as a package of yarn on the tube 160 at a rate of about 3800 meters / minute. The prepared POY has an elongation of 55 to 85%, preferably 75% and a toughness of 25 to 40 cN / tex, preferably about 30 cN / tex.

The present invention relates to synthetic polymer filaments having an "open hollow" profiled cross-section perpendicular to the longitudinal axis of the filament. The present invention further relates to spinneret plates for melt extrusion of filaments, and methods for producing filaments by melt extrusion.

1 is perpendicular to the longitudinal axis of the filament passing through the filament as long as it has dimensions R, F and D, lines R ₁ , R ₂ , reference point C, tangential reference line R _3, and a preferred cross-sectional shape representing each alpha (α). Represent the cross section.

2 shows a cross section perpendicular to the longitudinal axis of the filament through two adjacent filaments according to the invention.

Figure 3a is a plan view (constant ratio) in the form of a two-segment spinneret capillary cross section according to the present invention.

3B is a plan view (constant ratio) in the form of a one-segment spinneret capillary cross section in accordance with the present invention.

FIG. 4A is a yarn bundle micrograph of yarn cross section containing 26 filaments prepared by melt spinning from the spinneret capillary cross-sectional form of FIG. 3A in accordance with the present invention.

FIG. 4B is a yarn bundle micrograph of yarn cross section containing 26 filaments prepared by melt spinning from the spinneret capillary cross-sectional shape of FIG. 3B in accordance with the present invention. FIG.

5 is a schematic diagram of an apparatus for carrying out the fully drawn yarn (A) and POY (B) spinning method according to the present invention.

Test Methods

Water suction test method : The principle of this method involves suspending a strip of fabric vertically so that its lower end is submerged in water. The height of the water rising over the fabric was measured at fixed time intervals. Fabric samples taken were 300 mm long and 25 mm wide. Samples were conditioned for 16 hours at 85% +/- 5% relative humidity and 20 ° C +/- 2 ° C. The maximum rise height of 20 ° C. + / − 2 ° C. water was measured after 2 minutes. The height is measured from the surface of the water to the height on the fabric with the maximum water rise. The average value of three measurements for each vertical fabric direction was recorded.

Fabric Thickness Test Method : Fabric thickness is the average distance between the top and bottom surfaces of a material measured under specified pressure. The fabric samples were conditioned as in the case of moisture wicking. The measuring device used is a Shirley Thickness Guage with a 50 cm ² press foot. The press foot falls on the fabric under its own momentum. The measurement was repeated 10 times to record the mean and standard deviation closest to 0.05 mm.

Example 1

The first multifilament yarn (seal 1A) with 96 dtex and 26 filaments was spun as POY using the apparatus schematically shown in FIG. 5 and the spinneret plate with the two-segment capillary according to FIG. 3A.

Melt 10 nylon 66 polymer chip with 49.4 RV by formic acid method, through filter pack 20 and through spinneret plate 30 with 26 capillaries with segmented cross-sectional shape shown in FIG. 3A. Extruded at spinneret temperature of 280 ℃.

The newborn filament 40 was then cooled by a cross flow of air 50 with an air velocity of 0.45 meters / minute. The quench air was oriented to initially meet the facing lobes 38 of the two segment capillary, with reference to FIG. 3A. The cooled filaments 60 converged to the yarn at 70 and oil and water finish was added to the resulting yarn bundle at 70. The converged yarn to which the finishing agent was applied was advanced along path B of FIG. 5. The seal was passed through a vapor atmosphere containing interlayer tube 75. The steamed chamber 85 was mixed into the apparatus 80. The mixed yarn 115 was wound up in a package of yarn on tube 160 at a rate of 3800 meters / minute.

POY prepared in this manner had a solid line density of 96 decitex, an elongation at break of about 75% and a toughness of 30 cN / tex. The cross section of the yarn is shown in FIG. 4A.

A second multifilament partially oriented yarn (thread 1B) with 96 dtex and 26 filaments was spun exactly the same as the first POY using the apparatus schematically shown in FIG. 5. For yarn 1B, spinneret plates with capillaries according to FIG. 3B were used. Elongation and toughness characteristics were the same as for the first POY. The cross section of the yarn 1B is shown in FIG. 4B.

Spinning in the exact same way as the first yarn, except that the comparative multifilament yarn (seal 1C) with 96 dtex and 26 filaments was replaced with spinneret plates with 26 "circular cross-section" shaped capillaries. I was.

All samples, 1A and 1B (the yarn of the invention) and 1C (the comparative yarn of the circular cross section) are individually eight-ply and then air jet texturized using HEBERLEIN HEMAJET (registered trademark). (AJT) produced a textured yarn of 730 decitex x 208 filaments (8 x 26 filaments). These organized yarns were knitted in two layers into a "full cardigan structure" to test the thermal permeability.

The thermal permeability test method was essentially that of ASTM D1518-85 (reapproved in 1990). This method measures the rate of heat transfer time to a relatively calm, cold atmosphere above through a layer of cardigan test material knitted from a warm, dry constant temperature horizontal plate. The heat resistance was measured to calculate the thermal insulation or CLO value. "CLO" is equal to 0.155 (° C. m ² W ^-1 ) as a unit of "clothing heat resistance" in ASTM D1518. The substrate temperature was 25 ° C. (T ₁ ) and the hot plate temperature was 35 ° C. (T ₂ ). The minimum pressure applied to the cardigan knit during the test procedure was 260 Nm ⁻² . Each sample was tested three times to obtain an average result recorded in Table 1 below.

These test results, reported in Table 1, show a 13-15% increase in heat resistance in the case of the preferred open hollow cross section compared to the circular cross section yarn in the knit structure. Similarly, the CLO value for the open hollow cross section increased by 13-15% compared to the circular cross section yarn in the knit structure. Clearly, the open hollow filament yarn in the knit structure tested is a better thermal insulator than the circular filament yarn.

Thread used for cardigan knit Heat resistance m ² ℃ W ^-1 x (10 ³ ) CLO value m ² ° C W ^-1 /(0.155) ASTM D1518-85 Cross section of the present invention using yarn 1A (2 x 730f208) two segment spinneret 103.7 0.67 Cross section of the present invention with yarn 1B (2 x 730f208) 1 segment spinneret 105.0 0.68 Seal 1C (2 x 730f208) "Round" cross section 91.5 0.59

Example 2

POY samples from yarn 1A and comparative yarn 1C of Example 1 with 96 decitex and 26 filaments that were spun were subjected to Fall-Twist Texturing (FTT) at 600 meters / minute on a DCS 1200 texturing machine. The first heater of the texturing machine was 220 ° C. and no second heater was used. (78f26) draw-organized yarns with 78 decitex and 26 filaments were made from 6 mm solid ceramic disks of a texturing machine coordinated with 1/7/1 smoothing / working / smoothing. 78f26 yarn was circular knitted into 28 gauge plain knitting, washed with water, dyed and heat cured. A 300 mm × 25 mm fabric sample was taken and subjected to a water absorption test. These samples were suspended vertically into the water bath and after 2 minutes the vertical rise of water was measured. The average of three samples is provided in Table 2. Fabrics constructed from yarns with preferred cross-section filaments exhibited water wicking advantages over fabrics constructed identically from yarns with circular filament cross-sections. This advantage is a twofold improvement in water wicking capacity.

Organized thread used for circular knit Vertical rise in mm (longest direction of the fabric) Vertical rise in mm (shortest direction of the fabric) 78f26 comparative circular cross section (thread 1C) false twist organized thread 1.5 0 78f26 cross section of the present invention (thread 1A) false twist organized thread 3.7 2.7

Example 3

The drawing yarn with 192 decitex and 52 filaments was spun into the apparatus of FIG. 5 using a spinneret plate with 52 capillaries having the cross-sectional shape of FIG. 3A. Nylon 66 polymer with 49.4 RV (by formic acid method) was melted (10) and extruded through polymer filter pack 20 and then through spinneret 30 maintained at a temperature of 280 ° C. The extruded filaments 40 were cooled by a flow of alternating air 50 flowing at 0.4 meters / minute. The intersecting flow of air 50 was oriented to initially meet the facing lobes 38 of the two segment capillary shown in FIG. 3A. The cooled filaments converged into yarn bundles 60 to apply oil and water and were run along separate path A. The yarn was mixed with an air jet 80 as is typically practiced in the art. The mixed yarn 90 is then moved through the feed roll 92 and the associated separator roll (created several wraps on the roll to prevent slippage) at a surface speed that is 80% greater than the surface speed of the feed roll 92. Was fed to the second Godet 94 and the associated separator roll (stretch roll). The mixed yarn bundles 90 were stretched a total of 1.8 times to reduce the total amount of yarn. The stretching chamber 100 was treated by steam jet 110 to fix the stretching and to relax the yarn. The relaxed yarn bundle 120 was passed through a second knitting jet 130 and then the yarn 140 was wound on the tube 150 at a rate of 3800 meters / minute. This method provided a cake of fully drawn yarns (FDY) having a solid line density of 192 decitex, an elongation at break of about 42.8% and a toughness of 41 cN / tex. The yarn in dry form had an RV of 50.3 by the formic acid method. The filaments of these 52 filament yarns had a cross sectional shape perpendicular to the longitudinal axis substantially similar to the filaments shown in FIG. 4A.

This yarn, yarn 3A, was used as the weft of a 3/1 weave fabric, where the warp was 78 decitex (51 circular filaments). Detailed descriptions of weaving and fabric finishing are provided in Table 3. As a comparative example, a fully drawn yarn with 192 decitex and 52 filaments was spun in exactly the same manner as above except for using a spinneret plate having a "circular cross-section" capillary, which was called yarn 3B. The second fabric sample was woven using yarn 3B as weft as above. Detailed descriptions of weaving and fabric finishing are provided in Table 3. Both fabrics were equally finished in unbleached and dyed, dyed and heat cured forms. Ten samples of 75 square millimeters were cut from each fabric test piece (without bleaching and dyeing, dyed and thermoset). These samples were measured for fabric thickness in the same manner using micrometers. The results of the fabric thickness measurements (average of 10 measurements) are provided in Table 3. Fabrics containing cross-section filaments preferred for wefts were thicker than the thickness of the fabric in which the warp and weft yarns consist solely of circular cross-section filaments. As a result, fabrics with cross-sectional filaments preferred for wefts provided lower density fabrics with light weight aesthetics.

Not dyed or bleached fabric Not dyed or bleached fabric Dyed fabric Dyed fabric Thermoset fabric Thermoset fabric Thread 3B Thread 3A Thread 3B Thread 3A Thread 3B Thread 3A Warp end per cm × weft pick per cm 57.5 x 38.8 58.2 x 39.7 61.3 x 40 62.2 x 39.8 61.5 x 41 61.6 x 41 Fabric thickness millimeter 0.22 0.24 0.20 0.22 0.20 0.21

The above embodiments have been described by way of example only. Many other embodiments of the filaments, yarns, spinnerets and methods according to the present invention will be apparent to those skilled in the art.

Claims (38)

A release polymer filament having the form of an open hollow cross section perpendicular to the longitudinal axis of the filament, the cross section having the dimensions necessary to keep the filaments from intertwining with the second filament having the same cross section. A release polymer filament having a form of an open hollow cross section perpendicular to the longitudinal axis of the filament, wherein an area proximate each end of the cross section is wider than the gap between the areas forming an opening of the open hollow cross section. 3. The release polymer filament of claim 1 or 2, wherein the cross section includes an opening leading to the solid portion, the central hollow area and the central hollow area, wherein the opening is for a fan angle of less than 90 degrees. 4. The release polymer filament of claim 3, wherein the opening is for a fan angle of less than 60 degrees. 3. The cross section of claim 1 or 2, wherein the cross section comprises an opening leading to the solid portion, the central hollow region and the central hollow region, wherein in the region proximate to the opening the radial thickness of the solid portion of the filament cross section is defined by the solid region. Release polymer filaments larger than average radius thickness. 6. A base according to any one of the preceding claims, wherein the cross section has a base portion having first and second ends and two sides extending in a substantially parallel relationship from the first and second ends of the base portion. A release polymer filament comprising a portion. The release polymer filament of claim 6, wherein the base portion and the two side portions are arcuate. Having a cross-sectional shape perpendicular to the longitudinal axis of the filament, the cross-sectional shape having a central arcuate portion and first and second elongated leg portions, each leg portion having proximal and distal ends, wherein The proximal end is connected to the central portion, the distal end is connected to a foot portion having dimension F on each leg portion, the leg portion and the central arcuate portion form an open portion, and the foot portions are substantially A release polymer filament oriented in a parallel relationship to form an opening through the open portion, wherein the opening has a dimension D less than the dimension F. 3. The release polymer filament according to any one of claims 1 to 8, wherein the polymer is a polyamide. 10. The release polymer filament of claim 9, wherein the polyamide polymer has a relative viscosity by formic acid method greater than 40. 11. The release polymer filament of claim 10, wherein the relative viscosity of the polyamide with formic acid is in the range of 46 to 56. The release filament of claim 1, wherein the filament line density is less than 20 dtex. 13. The release filament of any of claims 1 to 12, wherein the filament line density is less than 4 dtex. The release filament of claim 1, wherein the filament cross section is substantially constant along the length of the filament. 15. The release filament of claim 1, wherein the polymer is selected from the group consisting of nylon 66 and nylon 6 and copolymers of nylon 66 or nylon 6. 16. Multifilament yarns wherein at least a portion comprises a release filament of any one of claims 1 to 15. 17. The multifilament seal of claim 16, wherein said seal consists essentially of open hollow filaments according to the present invention. 17. The multifilament yarn of claim 16 wherein said yarn is a stretched yarn. 19. The multifilament yarn of claim 18 wherein the yarn has an elongation at break of about 20-50% and a toughness of about 25-60 cN / tex. The multifilament yarn of claim 16 wherein said yarn is a partially oriented yarn (POY). The multifilament yarn of claim 20 wherein the yarn has an elongation at break of about 55 to 85% and a toughness of about 25 to 40 cN / tex. An article comprising at least a portion of the multifilament yarn of claim 16. The article of claim 22, wherein the article comprises a fabric knitted or woven from a multifilament yarn. A plate having upper and lower surfaces connected by capillary assemblies, wherein (a) each capillary has an open hollow transverse cross section, or (b) each capillary comprises two adjacent segments 22. Any of claims 1-21 by melt extrusion of the polymer into the filaments, wherein an open hollow filament cross section in the longitudinal direction is obtained with respect to the axis of the filament when the molten polymer streams from each segment merge at the point between the segments. Spinneret for producing a release-open hollow filament of claim. 25. The method of claim 24, wherein each capillary consists of two segments, each segment consisting of a straight length portion having a junction at each end with a pair of projecting portions, the pair of projecting portions being the same at the first end. A spinneret having an area, each comprising a straight portion ending in a rounded portion, and at the second end there are protruding portions having a pair of floating areas, each comprising a straight portion ending in a rounded portion. 27. The spinneret of claim 25, wherein each segment is a mirror image of another segment. 27. The spinneret of claim 26, wherein each segment is a mirror image that cannot be superimposed of another segment. The capillary of claim 24, wherein the capillaries themselves have an open hollow cross section, wherein each capillary A first straight portion having a first end and a second end facing each other; A second straight portion ending in a bifurcated portion and a third straight portion extending to the first two forked points from the first end of the first portion; A fourth straight portion and a fifth straight portion each extending from the first two forked points and ending with a round portion and having a floating area; A sixth straight portion ending in a bifurcated portion and a seventh straight portion extending to the second two forked points, bifurcated from the second end of the first straight portion; And An eighth straight portion and a ninth straight portion extending from the second two forks, each ending with a rounded portion and having a floating area; Spinneret having a cross-sectional shape comprising a. Extruding the polyamide melt through the spinneret of any one of claims 24 to 28; Cooling in an air stream across the extruded melt to form a solid filament; Passing the optionally quenched filament through a vapor atmosphere, applying fiber finishing oil, optionally knitting the yarn, passing the yarn over a pair of feed rolls and stretching rolls having a different surface speed by a fixed amount, Treating the drawn yarn to reduce final yarn shrinkage to form a good yarn package, optionally adding fiber finishing oil, knitting the yarn and winding the filament at a speed greater than 3000 meters / minute. A method of making a drawn yarn having a modified filament cross section as set forth in any one of claims 1 to 21. Extruding the polyamide melt through the spinneret of any one of claims 24 to 28; Cooling in an air stream across the extruded melt to form a solid filament; Passing the optionally quenched filament through a vapor atmosphere, applying fiber finishing oil, optionally passing the yarn over the tension control roll, optionally knitting the yarn and speeding the filament greater than 3000 meters / minute 22. A method of making a partially oriented yarn (POY) having a modified filament cross section of any one of claims 1 to 21, comprising winding into a furnace. 31. The method of claim 29 or 30, wherein the polymer is a polyamide having 40 to 60 RV (measured in formic acid). 31. The method of claim 29 or 30, wherein the spinneret temperature is about 245-295 ° C. 33. The method of any of claims 29-32, wherein the air velocity of the traversing air stream is between about 0.15 and 0.5 meters / minute. 34. The method according to claim 29, 31, 32 or 33, further comprising converging the cooled filaments into yarn bundles and winding the yarn bundles into a first goth (feed roll) before winding up the cooled filaments. Then sent to the second goth 94 (stretch roll) (at which time the second goth moves at a surface speed of 10 to 100% greater than the surface speed of the feed roll, stretching the yarn and thus the total amount of yarn Reduction), and a method of treating the stretched yarn as heat treating to fix the stretch and relax the yarn. 34. The method according to any one of claims 30 to 33, further comprising converging the cooled filaments into yarns and running the condensed yarns through a vapor atmosphere-containing interlayer tube before steaming the cooled filaments Treated yarns by mixing, winding and providing partially oriented yarns (POY). An air jet organized multifilament yarn made from the stretching yarn of claim 18. An air jet organized multifilament yarn made from the partially oriented yarn of claim 20. A twist twist organized (FTT) multifilament yarn made from the partially oriented yarn of claim 20.